For the fourth year in a row, the number of people expected to travel over the Thanksgiving holiday is expected to increase, said Fran Mayko, spokeswoman for the AAA/Connecticut Motor Club. They'll be paying about 20 cents less at the pump than they would have a month ago, but still 12 cents more per gallon than last Thanksgiving, according to the national Lundberg Survey.

"Prices are still too high, but I'll take any help I can get," said John Franklin, 34, as he filled up his tank at the Shell gas station on the Post Road in Fairfield on Tuesday evening, getting ready for a trip to visit family in Maryland. "I know traffic is going to be terrible, and there's nothing that I can do about that, so at least I'll be paying a little less."

Gas prices have skidded since late October due to increasing stockpiles, lower demand and the effects of Hurricane Sandy on travel, according to analyst Trilby Lundberg. The national average price per gallon is $3.55; Connecticut prices are about 20 cents higher per gallon due to taxes.

Greg Norwood, of Stamford, said he was traveling to Long Island for Thanksgiving dinner at his parents' house in Manorville, though he was conscious of gas prices in planning his driving trips.

About 90 percent of the 46.5 million people with holiday travel plans will be driving, Mayko said. The number of people flying is down from last Thanksgiving by 1.7 percent, she said, but that still leaves more than 3 million jamming airports and lining up at the baggage scanners.

This year's auto travelers will average about 588 miles round trip, and 75 percent will stay with family and friends, Mayko said. About half expect to leave Wednesday, the AAA survey shows.

The Thanksgiving holiday traditionally kicks off a season of stepped-up enforcement of drunken driving laws.

In Stratford, and several other area towns, police will be increasing patrols and conducting roadside sobriety checkpoints for impaired driving during this holiday season, Lt. Frank Eannotti said.

The effort begins Wednesday and will continue into the new year, he said. The sobriety checkpoints are scheduled for Nov. 30 and Dec. 29 from 8 p.m. to 4 a.m.

Last year, state troopers cited 1,376 drivers for speeding, 417 for seat belt violations, 2,745 for hazardous moving violations and made 65 driving under the influence arrests during Thanksgiving weekend. There were 389 accidents, including two fatal crashes and 50 with injuries.

"Motorists need to remember: Don't follow too close, slow down, stay off your cellphone and if you drink, then don't drive," said Vance.

Sobriety checkpoints and roving DUI patrols will be set up by troopers around the state throughout the weekend. Uniformed troopers will use non-traditional patrol cars to observe traffic and issue tickets to reckless and distracted drivers, Vance said.

To keep up with a trend of increasing ridership on Thanksgiving weekend in recent years, Metro-North is continuing to add new getaway trains running Wednesday afternoon out of New York City, spokesman Aaron Donovan said.

Ridership out of Grand Central Terminal is typically 20 to 25 percent higher than normal between noon and 8 p.m. on the Wednesday before Thanksgiving, with 40,000 customers leaving between noon and 4 p.m. last Thanksgiving's Eve when Metro-North. Metro-North projects to add another four percent, or 800 riders to the 20,000 more than normal number of passengers who traveled from the Terminal the between noon and 8 p.m. last Thanksgiving Eve, Donovan said.

There will be extra New Haven Line trains into Grand Central Terminal on Thursday morning to accommodate people going to New York City for the Macy's Thanksgiving Day parade, and additional outbound trains in the evening. Trains will operate on a Saturday schedule on Friday, with extra service for Black Friday shoppers, according to the railroad's website. Up-to-date schedule information is available on the Metropolitan Transportation Authority website.

John Wallace, a spokesman for Bradley International Airport, said while the two-terminal airport has been busy for the past four days and should remain so through next Tuesday, traffic there has fallen about 5 percent year over year.

Wallace said the decline in air passenger travel at Bradley and other regional airports is in significant part due to smaller, fuller aircraft and fewer flights overall.

"As far as numbers, they haven't been the greatest for the past 10 months, but we've seen a significant uptick and been very steady and busy throughout the past few days," he said.

The weather will be pleasant throughout most of the long holiday weekend, though it will be colder after a front comes through Saturday, bringing isolated showers, said WTNH meteorologist Gil Simmons. Daytime highs in the low to mid-50s will drop by 10 degrees, to 41 on Sunday. The temperature will dip below freezing inland Sunday night, according to Simmons.